1. Field of the Invention
This invention relates to detecting biological toxins and, more particularly, to a method for amplifying genes coding for the toxins and detecting the amplified genes, which detection is indicative of the presence of the toxins.
2. Description of the Related Art
The ability to detect the presence or absence of biological toxins, such as botulin (a toxin produced by the bacteria Clostrium botulinum) or aflatoxins (a toxin produced by the fungus Aspergillus favus) contaminating food, various biological warfare agents contaminating the air, and various contaminants of water or biological samples, has been a desire of scientists for ages. Such an ability would help prevent disease, incapacitation or other maladies attributable to the toxins, and would be useful in countering the use of biological weapons.
Current tests for detecting toxins usually depend on chromatographic techniques, such as gas or high-pressure-liquid chromatography, mass spectroscopy, in vivo tests or in vitro bioassays. In vivo tests involve injecting the toxin into animals, usually mice, at varying doses to determine lethality. In vitro bioassays rely on the use of an antibody, receptor or living cell that binds the toxin directly. Thus, the actual toxin is sought to be detected.
In other cases, assay methods are used to detect an organism which is the source of the toxin. For example, if a pathogenic organism is known to be associated directly with a toxin, tests have sought to detect the presence of the pathogen. Such tests may include culturing the live organism.
The conventional tests described above generally are not very sensitive. They also may require pre-concentration of a sample suspected of containing the toxin or organism. Further, in some cases, at least partial purification is necessary to remove interfering substances. These steps can be time-consuming and costly.
To date, there has not been developed a quick and efficient method for detecting the presence of a biological toxin in a sample, said detection being possible even if the toxin has been denatured or the organism responsible for producing the toxin is no longer present.